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Biomedical subjects

D Y Mason

Publications and source records attributed to D Y Mason.

At least 307 records · Page 17Linked to original sources
PubMed1979

The distribution of HLA on human lymphoid, bone marrow and peripheral blood cells.

The cellular distribution and the differential expression of HLA on cell suspensions and tissue sections has been investigated using the monoclonal antibody W6-32, which reacts with the high molecular weight chain of the major histocompatibility antigen. Lymphocytes and platelets, as assessed by autoradiographic and immunoperoxidase labeling, were the most densely labeled cells. Myeloid precursors showed more labeling than mature neutrophils. Electron microscopic immunoperoxidase labeling showed a continuous distribution of HLA antigen on lymphoid and myeloid cell membranes. Erythroid precursors (including reticulocytes), although very weakly labeled, were clearly positive, in comparison with mature erythrocytes. In the thymus, HLA-negative, thymocyte antigen-positive cells (85%) can be distinguished from HLA-positive, thymocyte antigen-negative cells (15%). By using immunofluorescence techniques on tissue sections, the former cells were shown to be cortical thymocytes and the latter medullary cells.

Antigens, Surface↗
PubMed1979

The labeled antigen method of immunoenzymatic staining.

A two stage immunohistological technique (the "labeled antigen" procedure) has been assessed for the detection of a variety of human and animal cytoplasmic constituents in tissue sections. In this method specific antiserum is followed by antigen complexed to horseradish peroxidase or to alkaline phosphatase. The primary antibody acts bivalently, linking the labeled antigen to antigen in the tissue section. The major advantage of this technique is that nonantigen specific antibody in the primary antiserum cannot cause nonspecific staining since it has no affinity for the antigen:enzyme complex. Consequently the specificity of the reaction is assured, background staining is minimized and the total staining time (from wax section to mounted slide) can be reduced to as little as 30 min. Further advantages include the possibility of labeling Ig allotypes and the high efficiency of enzyme utilization. Covalent human IgG:horseradish peroxidase complexes can also be used in a triple sandwich in conjunction with human anti-viral or autoimmune antibodies.

Alkaline Phosphatase↗
PubMed1978

Rapid preparation of peroxidase: anti-peroxidase complexes for immunocytochemical use.

Soluble immune complexes of horseradish peroxidase and antibody to peroxidase (PAP) have been widely used in the 'unlabelled antibody' method for the immunocytochemical detection of cellular antigens. This paper describes a simple and rapid method for preparation of these complexes by column chromatography of a mixture of the enzyme and the IgG fraction of antiperoxidase antiserum on Sephacryl S-200. The material eluting in the void column consists of stable soluble PAP complexes, with a molar peroxidase: antiperoxidase ratio of 0.8 and a molecular weight of approximately 400,000. When tested immunocytochemically this material gives identical results to those obtained with conventionally prepared PAP.

Animals↗
PubMed1978

Distribution of transferrin, ferritin, and lactoferrin in human tissues.

An immunoperoxidase staining technique was used for detecting three major iron-binding proteins (transferrin, ferritin, and lactoferrin) in routine histological paraffin sections of human tissue. Transferrin was found mainly in hepatocytes, a variety of epithelial and myoepithelial cells, renal tubular cells, and histiocytes. Ferritin was most readily found in histiocytes and liver cells, with weaker reactions seen in epithelial cells. Lactoferrin was found in lactating breast tissue, bronchial glands, polymorphs, and gastric and duodenal epithelial cells. The technique is potentially valuable for investigating abnormal iron states.

Female↗
PubMed1978

Alkaline phosphatase and peroxidase for double immunoenzymatic labelling of cellular constituents.

The use of alkaline phosphatase in an immunoenzymatic procedure for the localisation of antigens in paraffin sections or cell smears is described. The results of this method, when applied to the detection of immunoglobulins, lysozyme, or lactoferrin, were comparable in intensity and clarity to those obtained with the PAP immunoperoxidase procedure. Furthermore, double immunoenzymatic labelling (with alkaline phosphatase and peroxidase) of two cellular constituents in a tissue section is possible, the brown peroxidase reaction product contrasting well with the blue alkaline phosphatase product. Since the two antibody 'sandwiches' are applied simultaneously rather than sequentially the total duration of this double immunostaining procedure is only a few minutes longer than that required for detection of a single antigen. It was also found that the unlabelled antibody immunohistological procedure (whether used in conjunction with alkaline phosphatase or peroxidase) can be shortened without loss of sensitivity by carrying out two of the incubation steps simultaneously.

Alkaline Phosphatase↗
PubMed1977

Intracellular lysozyme and lactoferrin in myeloproliferative disorders.

Samples from 49 cases of myeloproliferative diseases were tested by an immunocytochemical technique for leucocyte lysozyme and lactoferrin. The presence of these constituents in myeloid precursors from cases of acute and chronic myeloid leukaemia reflected the degree of cellular maturation, lysozyme appearing (as it does in normal myeloid cells) at the stage of primary granule production (in promyelocytes), while lactoferrin wad detectable only in more mature, secondary granule-containing myeloid cells. Auer rods stained positively for lysozyme, in keeping with their relationship to primary granules. Monocytes from five cases of leukaemia showing predominantly monocytic differentiation were indistinguishable from normal monocytes in their staining reactions for lysozyme despite the presence of raised serum and urinary lysozyme levels. In four cases of acute myeloid leukaemia circulating polymorphs deficient in lactoferrin were detected: in one of these cases a similar percentage of polymorphs was lysozyme negative.

Humans↗
PubMed1977

The detection of membrane and cytoplasmic immunoglobulins in human leucocytes by immunoperoxidase staining.

A sensitive immunoperoxidase technique for the detection of immunoglobulin (the peroxidase--anti-peroxidase or PAP procedure) has been applied to fixed smears of normal human white cells. IgM was detected in approximately 5% of lymphocytes from normal donors. Most positive cells showed a characteristic 'hairy' peripheral staining pattern; a similar morphological appearance was seen in samples stained for IgD. The membrane (rather than cytoplasmic) localization of this IgM was inferred from the redistribution of staining induced by preliminary incubation of cell suspensions with anti-mu antisera before smearing and staining. B cell-depleted and B cell-enriched suspensions showed, respectively, reduced and increased percentages of IgM-positive cells. IgG was detectable in approximately 25% of normal lymphoid cells. In contrast to the IgM and IgD reaction patterns, these cells commonly showed a discontinuous distribution of reactivity, often localized to the cell uropod or to small cytoplasmic vesicles. However, when cells were prepared at 0 degree C, staining tended to be diffuse. These findings suggested that the PAP procedure was detecting Fc receptor-bearing lymphoid cells which had bound serum IgG. IgG was also demonstrated in normal polymorphs and monocytes. The specificity of this reaction was confirmed by the use of immunoabsorbant-purified antibodies. The possible practical advantages of this immunoperoxidase procedure for the detection of leucocyte immunoglobulin are considered, and the relevance of the demonstration of IgG in non-lymphoid cells to recent reports of this immunoglobulin in Hodgkin's disease and malignant 'reticulum' cells is briefly discussed.

Cytoplasm↗
PubMed1976

Disseminated intravascular thrombosis as the cause of ischaemic enterocolitis.

Disseminated intravascular thrombosis was diagnosed in a woman aged 63 years. At autopsy the typical appearances of ischaemic enterocolitis were found, together with thrombi in other organs. This case illustrates the previously postulated connection between intravascular thrombosis and ischaemic enterocolitis.

Disseminated Intravascular Coagulation↗
PubMed1976

Waldenström's disease of the jejunum.

A case of Waldenströms macroglobulinaemia with characteristic clinical features was investigated in life and at autopsy. Using immunochemical and immunohistochemical methods it was confirmed that the abnormal clone of cells producing IgM formed a solitary tumour in the jejunum causing partial obstruction. Resection of the tumour led to an improvement in the clinical condition and biochemical measurements.

Aged↗
PubMed1976

Relationship between paraprotein polymerization and clinical features in IgA myeloma.

The clinical manifestation fo IgA multiple myeloma are usually not considered distinguishable from those of IgG myeloma despite the fact that IgA differs from IgG in several characteristics, particularly molecular size heterogeneity. The clinical and laboratory features of 25 patients with IgA myeloma seen during a 5 year period are presented. The degree of paraprotein polymerization was observed to vary greatly in these patients but remained chronologically constant in six individuals studied on several occasions over this period. The patients were divided into two groups on the basis of the degree of paraprotein polymerization. The first group comprised those patients in whom the IgA paraprotein was greater than 50% polymerized, whilst in the second group the paraprotein was predominantly monomeric. No clinical or pathological differences were seen between the 'polymeric' and 'monomeric' groups of myeloma apart from that directly attributable to the physicochemical effect of the paraprotein polymerization. Thus, five patients out of 11 of the 'polymeric' group had developed the hyperviscosity syndrome, whilst no patients in the 'monomeric' group had developed this complication. The concentration of the paraprotein during the course of the disease was comparable in both groups. This syndrome is considered to be relatively common in IgA myeloma and adds to the morbidity and mortality of the disease. Its anticipation and treatment may improve the quality and survival of patients likely to develop this complication.

Adult↗
PubMed1976

Monocyte ingestion of IgG-coated erythrocytes from haemolysing and non-haemolysing subjects.

A number of individuals in the population, including healthy blood donors and patients on methyldopa, show evidence erythrocyte coating by IgG autoantibodies (postive direct Coombs' test) without signs of a haemolytic state. The readiness with which red cells from these subjects are taken up by normal human monocytes in short term culture was examined, and compared with the phagocytosis of red cells from cases of IgG-mediated haemolytic anaemia. Red cells from non-haemolysing subjects were as avidly ingested in this system as were red cells from haemolysing patients. Similar results were obtained using normal red cells sensitised with antoantibody eluted from the cells of a healthy blood donor.

Anemia, Hemolytic, Autoimmune↗
PubMed1975

The detection of intracellular antigens in human leucocytes by immunoperoxidase staining.

An immunoperoxidase procedure is described for staining intracellular leucocyte antigens in peripheral blood and bone marrow smears. Brief exposure of cell smears to a buffered formol acetone mixture was found to give optimal fixation, combining good cellular morphology with preservation of antigenic reactivity. The immunoperoxidase method is superior to immunofluorescence in that it provides a permanent preparation which can be counterstained with orthodox reagents and viewed by conventional light microscopy. In addition the technique is considerably more sensitive than immunofluorescence procedures. Immunoglobulin was demonstrated in plasma cells, Türk cells and a minority of peripheral blood lymphocytes. Lysozyme was found in cells of the neutrophil series from promyelocytes to mature granulocytes. Monocytes stained for lysozyme but the reaction was less intense than in neutrophils and some monocytes were devoid of activity. Lactoferrin stained strongly in mature neutrophil polymorphs and metamyelocytes, but was weak or absent in earlier myeloid cells. These reaction patterns are in keeping with previous reports on the distribution of these antigens in human leucocytes. In the case of immunoglobulin and lysozyme it was possible to abolish leucocyte staining by incubation of the specific antisera with the appropriate purified antigen, providing additional proof of the specificity of the reactions. Anti-ferritin antisera stained granulocytes and myeloid precursors strongly, and reached weakly with a minority of monocytes. These latter observations are not entirely in accordance with published data on the leucocyte distribution of ferritin and may be attributed to antibody activity of unknown specificity in the anti-ferritin antiserum.

Antigens↗
PubMed1975

HL-A antigen frequencies in myeloma.

The frequency of HL-A antigens was determined in 63 myeloma patients and in 83 normal subjects. HL-A5 was more frequent among patients (15.9%) than among controls (3.6%). This association was significant at the 0.05 level, but the significance did not survive multiplication by the number of antigens under study. The relationship of these findings to previous work on myeloma is discussed, together with the problems of defining components of the 4c antigenic group.

Adolescent↗
PubMed1975

The distribution of muramidase (lysozyme) in human tissues.

The distribution of muramidase (lysozyme) in normal and pathological human tissues has been studied, using an immunohistological technique. The enzyme was demonstrated in a variety of healthy tissues, including serous salivary acinar cells, lactating mammary tissue, Paneth cells, renal tubular cells, myeloid cells (including eosinophils), and histiocytic cells. In pathological tissues the most striking positivity was encountered in reactive histiocytic cells in granulomatous conditions such as tuberculosis and Crohn's disease. The finding of this study are related to previous reports of the distribution of human and animal muramidase and the implications of patterns of muramidase staining in pathological histiocytes are briefly discussed.

Bone Marrow↗